Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(?<=\d{4}\-\d{2}\-\d{2}|\d{4}.\d{4}|\d{4}.\d{1}.\d{1}.\d{2}|\d{4}.\d{2}.\d{2}).*?(?=\d)", flags=re.MULTILINE) test_str = (". FIRST BANK OF WIKI\n" ", 1425 JAMES ST, PO BOX 4000 CHEQUING ACCOUNT STATEMENT\n" "VICTORIA BC V8X 3X4 1-800-555~5555 Page: 1 of 1\n" "JOHN JONES I Sififi3331‘3311 Erma II EEK-111313010: I\n" "1643 DUN DAS ST W APT 27 2003-10-09 to 200341-08 00005-\n" "TORONTO ON M6K 1V2 123-4567\n" "I sue II 1% 1::ng “W II um II I\n" "2003-10-08 Previous balance 0.55 I\n" "2003-10-14 Payroll Deposit - HOTEL 694.81 695.36\n" "2003-10-14 Web Bill Payment - MASTERCARD 9685 200.00 495.36 \n" "2003—1046 ATM Withdrawal - INTERAC 3990 21 .25 474.11 .\n" "2003-10-16 Fees - lnterac 1 .50 472.61 I\n" "2003-10-20 Interac Purchase - ELECTRONICS 1975 2.99 469.62 .\n" "2003-10-21 Web Bill Payment - AMEX 3314 300.00 169.62\n" "2003-1 0-22 ATM Withdrawal - FIRST BANK 0064 100.00 69.62 .\n" "2003-10-23 lnterac Purchase - SUPERMARKET 1 559 29.08 40.54 I\n" "2003-10-24 Interac Refund - ELECTRONICS 1975 2.99 43.53\n" "2003-10-27 Telephone Bill Payment — VISA 2475 6.77 36.76 I\n" "2003-1328 Payroll Deposit - HOTEL 694.81 731.57 .\n" "2003-10~30 Web Funds Transfer - From SAVINGS 2620 50.00 781.57 I\n" "2003-11-03 Pre-Auth. Payment - INSURANCE 33.55 748.02 .\n" "2003-11-03 Cheque No. - 409 1 00.00 648.02\n" "2003-11-06 Mortgage Payment 710.49 -62.47 .\n" "2003-11-07 Fees - Overdraft 5.00 -67.47 I\n" "2003-11-08 Fees - Monthly 5.00 -72.47\n" "*** Totals m 1 ,515.63 1,442.61 I") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html